The research project will evaluate factors involved in the regulation of the hypothalamic-pituitary axis and in the pubertal maturation of the hypothalamic-pituitary-gonadal system. The effects of diets specifically deficient in single elements such as trace metals (zinc, manganese, magnesium, et cetera), amino acids, fatty acids and vitamins upon hypothalamic-pituitary function will be studied in fetal, prepubertal and pubertal animals and compared to ad-lib or pair-fed control animals ingesting complete diets. The effects of hypothalamic releasing hormones will be studied in such animals. The role of the pineal gland in the regulation of the hypothalamic-pituitary axis will be studied by observing the effects of administering melatonin and other pineal products to rats. Generation of antisera to melatonin will be attempted. Antisera will be employed to establish a radioimmunoassay for melatonin and to observe the effects of neutralization of melatonin upon hypothalamic-pituitary function. Antisera to luteinizing hormone-follicle stimulating hormone and to prolactin will be administered to rats and their effects on pituitary-gonadal function studied. An attempt to produce antisera against luteinizing hormone-releasing hormone will be undertaken. If successful these antisera will be utilized to establish a radioimmunoassay for LH-RH and to evaluate the effects of neutralization of this hypothalamic peptide upon pituitary function. Collaborative studies of the effects of inhibition of steroidogenesis and of the regulation of growth hormone secretion will be continued. Further measurements of serum levels of immunoreactive parathyroid hormone will be in normal and abnormal subjects.